Detecting Device and Detecting Method

ABSTRACT

A detecting device for detecting a stack light state is disclosed. The detecting device comprises a low-pass filter configured to perform low-pass filtering on an input signal to generate a first output voltage; and a logic circuit coupled to the low-pass filter and configured to determine the stack light state according to the first output voltage; wherein the input signal is a pulse width modulation signal and a voltage level of the first output voltage is between a highest voltage level and a lowest voltage level of the pulse width modulation signal.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to a detecting device and detectingmethod, and more particularly, to a detecting device and detectingmethod capable of detecting a control signal of a stack light so as todetermine a state of the stack light.

2. Description of the Prior Art

In a conventional environment of industrial internet of things, manydevices and machines are equipped with multi-color stack light displaysfor displaying current states of the devices and machines, wherein themost common stack light displays are with red, yellow and green.Therefore, there is a trend to perform big data collection and analysisfor the stack light states of the stack light displays. In general,there are three states of the stack light displays, such as persistenton, persistent off and twinkling. It is difficult to determine the stacklight state when detecting the state of the twinkling stack lightdisplay, since the twinkling state of different stack light displays arenot identical, especially when the twinkling frequency is discordant ora time period of the persistent on/off of the stack light displays aredifferent. In addition, in order to correctly determine the twinklingfrequency of the stack light displays, a period of time is needed tocalculate a number of repeat times of the stack light being on and off.For example, the stack light display is determined as twinkling when thestack light display is on and off for at least twice in a period oftime. In other words, under a situation of the stack light is on for 2seconds and off for 2 seconds respectively, 8 seconds is needed tocalculate the number of repeat times of the stack light being on andoff, such that the twinkling state of the stack light display can bedetermined, which causes wastes and damages of costs to the environmentof industrial internet of things in pursuing a real-time reporting ofthe devices. Therefore, there is a necessity to improve the conventionaldetecting method for the stack light.

SUMMARY OF THE INVENTION

Therefore, the present invention provides a detecting device and adetecting method using the same for a stack light, which utilizes acontrol signal of the stack light to correctly determine an outputsignal of the twinkling stack light, and effectively determine the stacklight state and realize a real-time detection.

The present invention discloses a detecting device for detecting a stacklight state, comprising a low-pass filter configured to perform low-passfiltering on an input signal to generate a first output voltage; and alogic circuit coupled to the low-pass filter and configured to determinethe stack light state according to the first output voltage; wherein theinput signal is a pulse width modulation signal and a voltage level ofthe first output voltage is between a highest voltage level and a lowestvoltage level of the pulse width modulation signal.

The present invention further discloses a detecting method for detectinga stack light state, comprising performing low-pass filtering on aninput signal to generate a first output voltage; and determining thestack light state according to the first output voltage; wherein theinput signal is a pulse width modulation signal and a voltage level ofthe first output voltage is between a highest voltage level and a lowestvoltage level of the pulse width modulation signal.

These and other objectives of the present invention will no doubt becomeobvious to those of ordinary skill in the art after reading thefollowing detailed description of the preferred embodiment that isillustrated in the various figures and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a detecting device according to anembodiment of the present invention.

FIG. 2 is a schematic diagram of a pulse width modulation signal.

FIG. 3 is a schematic diagram of a first output voltage according to anembodiment of the present invention.

FIGS. 4-6 are schematic diagrams of a detecting device according toembodiments of the present invention.

FIG. 7 is a schematic diagram of a detecting method according to anembodiment of the present invention.

DETAILED DESCRIPTION

Please refer to FIG. 1, which is a schematic diagram of a detectingdevice 10 according to an embodiment of the present invention. Thedetecting device 10 may detect a stack light state of a device or amachine in an environment of industrial internet of things, whichincludes a low-pass filter 102 and a logic circuit 104. The low-passfilter 102 includes a resistor R1 and a capacitor C1, and is configuredto perform low-pass filtering on an input signal Vin, so as to generatea first output voltage V1. In this embodiment, the input signal Vin maybe a control signal related to the stack light, e.g. a pulse widthmodulation (PWM) signal, and the first output voltage V1 may be adirect-current (dc) voltage. The logic circuit 104 is coupled to thelow-pass filter 102 and configured to determine the stack light stateaccording to the first output voltage V1, wherein the first outputvoltage V1 is between a highest voltage level and a lowest voltage levelof the PWM signal. Therefore, the low-pass filter 102 of the presentinvention may convert the PWM control signal, which is related to thestack light, into the first output voltage V1, and the logic circuit 104may simultaneously determine an on/off state of the stack light.

In detail, the low-pass filter 102 may perform the low-pass filtering onthe PWM control signal of the stack light, i.e. the input signal Vin, soas to generate the first output voltage V1, which is close to the dcvoltage, and outputted dc voltage levels corresponding to the PWMcontrol signals with different frequencies are different. Therefore,when the stack light state is persistent on or off, the PWM controlsignal is maintained at the highest voltage level or the lowest voltagelevel for a long period. Since the period of the stack light beingpersistent on or off is larger than times of an RC time constant of thelow-pass filter 102. Under this situation, the first output voltage V1generated by the low-pass filter 102 is in accordance with the highestvoltage level or the lowest voltage level of the PWM control signalsince the capacitor C1 of the low-pass filter 102 is fully charged orfully discharged. That is, when the PWM control signal is maintained atthe highest voltage level and the lowest voltage level for a longperiod, the stack light state may be respectively determined aspersistent on and off accordingly.

Assume that a range of twinkling frequency of the stack light is between0.25 Hz and 10 Hz, under this circumstance, the detecting device 10first determines a dc voltage value of the first output voltage V1 ofthe PWM control signal passing through the low-pass filter 102, whereina range of the dc voltage value of the first output voltage V1 isbetween the highest voltage level and the lowest voltage level of thePWM control signal. Then, the logic circuit 104 determines the voltagevalue of the first output voltage V1 so as to determine whether thevoltage value of the first output voltage V1 is in the correspondingrange of twinkling frequency of the stack light accordingly. Therefore,without spending extra time for calculating a number of times of the PWMcontrol signal converting between the highest level and the lowestlevel, the stack light state is determined, an effect of reporting thestack light state in real-time is achieved.

For example, please refer to FIG. 2, which is a schematic diagram of apulse width modulation signal. As shown in FIG. 2, the PWM controlsignal has a highest voltage level VH and a lowest voltage level VL.Notably, in this example, the lowest voltage level VL may be 0V. Whenthe stack light state is persistent on or persistent off, the PWMcontrol signal is maintained at the highest voltage level or the lowestvoltage level for a long period. Therefore, when the PWM control signalis maintained at the highest voltage level VH, i.e. the stack light isin the persistent on state. In contrast, when the PWM control signal ismaintained at the lowest voltage level VL (e.g. 0V), the stack light isin the persistent off state. In addition, the dc voltage levelcorresponding to the first output voltage V1 varies when the PWM controlsignals with different twinkling frequencies pass through the low-passfilter 102. Please refer to FIG. 3, which is a schematic diagram of thefirst output voltage V1 according to an embodiment of the presentinvention. The first output voltage V1 is between the highest voltagelevel VH and the lowest voltage level VL (e.g. 0V). When the twinklingfrequency is higher (e.g. 10 Hz), the corresponding dc voltage levelV_(10 Hz) is lower, a charging/discharging time of the capacitor C1 ofthe low-pass filter 102 is shorter, and as a result, a generated rippleamplitude is smaller. In contrast, when the twinkling frequency is lower(e.g. 0.25 Hz), the corresponding dc voltage level V_(0.25 Hz) ishigher, the charging/discharging time of the capacitor C1 of thelow-pass filter 102 is longer, and thus, the generated ripple amplitudeis larger.

Therefore, when the dc voltage level of the first output voltage V1(i.e. the PWM control signal after the low-pass filtering of thelow-pass filter 102) corresponds to the twinkling frequencies between0.25 Hz and 10 Hz, the stack light is in the persistent on state.Similarly, when the dc voltage level of the first output voltage V1 ishigher than the dc voltage level V_(0.25 Hz) corresponding to thetwinkling frequency at 0.25 Hz, the stack light is in the persistent onstate; when the dc voltage level of the first output voltage V1 is lowerthan or equal to the dc voltage level V_(10 Hz) corresponding to thetwinkling frequency at 10 Hz, the stack light is in the persistent offstate. Therefore, the low-pass filter 102 of the detecting device 10performs the low-pass filtering on the PWM control signal, so as todetermine the stack light state according to the voltage level of thefirst output voltage V1 in real-time.

In brief, the low-pass filter 102 of the detecting device 10 of thepresent invention converts the control signal of the stack light intothe first output voltage V1, which is close to the dc voltage, so as todetermine the on/off state of the stack light, and provide detectingresults in real-time. Notably, those skilled in the art may make propermodifications to the detecting device of the present invention accordingto different system requirements, and not limited thereto, which allbelong to the scope of the present invention.

Please refer to FIG. 4, which is a schematic diagram of a detectingdevice 40 according to an embodiment of the present invention. In thisembodiment, the detecting device 40 includes a low-pass filter 402 and alogic circuit 404. Different with the detecting device 10, the logiccircuit 404 includes voltage comparators 406, 408 and a processor 410.The voltage comparators 406, 408 are utilized for converting a firstoutput voltage V1 generated by the low-pass filter 402 into a pluralityof logic results. Then, the processor 410 determines the stack lightstate accordingly. In this embodiment, the voltage comparators 406, 408are respectively utilized for determining relationships between thefirst output voltage V1 with the voltage level V_(0.25 Hz) and thevoltage level V_(10 Hz). The processor 410 may include a general-purposeinput (GPI) pin, so as to determine a voltage level of an output voltageVout, e.g. a high voltage level or a low voltage level. Morespecifically, the voltage comparator 406 is utilized for determiningwhether the voltage level of the first output voltage V1 is lower thanthe voltage level V_(0.25 Hz) or not, i.e. the voltage levelcorresponding to the twinkling frequency at 0.25 Hz. When the outputtedlogic result is YES, the voltage comparator 406 outputs the high voltagelevel; that is, the current twinkling frequency of the stack light ishigher than 0.25 Hz. Similarly, the voltage comparator 408 is utilizedfor determining whether the voltage level of the first output voltage V1is higher than voltage level V_(10 Hz) or not. When the outputted logicresult is YES, the voltage comparator 408 outputs the high voltagelevel; that is, the current twinkling frequency of the stack light islower than 10 Hz. Therefore, with a design of logic AND at the outputpins of the voltage comparator 406 and the voltage comparator 408, whenthe output voltage Vout is at the high voltage level, which representsthat a variation frequency of the PWM control signal is between 0.25 Hzand 10 Hz, the processor 410 may determine that the stack light is inthe twinkling state accordingly. When the output voltage Vout is at thelow voltage level (i.e. at least one of the outputted logic resultsamong the voltage comparators 406, 408 is at the low voltage level)which represents that the variation frequency of the PWM control signalis higher than 10 Hz or lower than 0.25 Hz (i.e. the stack light stateis persistent on/off), the processor 410 determines that the stack lightis in an non-twinkling state accordingly. As a result, logic relationsbetween the first output voltage V1, the output voltage Vout and thestack light state may be inducted and shown in Table 1.

TABLE 1 V1 GPI The stack light state ~VH L Non-Twinkling VH > V1 ≥V_(0.25 Hz) L Non-Twinkling V_(0.25 H) > V1 ≥ V_(10 Hz) H TwinklingV_(10 Hz) ≥ V1 > VL L Non-Twinkling ~VL L Non-Twinkling

In another embodiment, please refer to FIG. 5, which is a schematicdiagram of a detecting device 50 according to an embodiment of thepresent invention. In this embodiment, the detecting device 50 includesa low-pass filter 502 and a logic circuit 504, wherein the logic circuit504 includes voltage comparators 506, 508 and a processor 510. Differentwith the detecting device 40, the processor 510 includes pins GPI 1, GPI2 to determine the stack light state according to voltage levels ofoutput voltages Vout 1, Vout 2 of the voltage comparators 506, 508. Morespecifically, when the voltage level of a first output voltage V1 ishigher than that of V_(0.25 Hz), i.e. the pin GPI 1 is at a low voltagelevel, and the pin GPI 2 is at a high voltage level, the stack light isin the persistent on state. When the pin GPI 1 is at the high voltagelevel, and the pin GPI 2 is at the low voltage level, the stack light isin the persistent off state. When the pins GPI 1, GPI 2 are at the highvoltage level at the same time, the stack light is in the twinklingstate. Therefore, the logic relations between the first output voltageV1, the output voltage Vout and the stack light state may be inductedand shown in Table 2.

TABLE 2 V1 GPI_1 GPI_2 The stack light state ~VH L H Persistent On VH >V1 ≥ V_(0.25 Hz) L H Persistent On V_(0.25 H) > V1 ≥ V_(10 Hz) H HTwinkling V_(10 Hz) ≥ V1 > VL H L Persistent Off ~VL H L Persistent Off

In another embodiment, please refer to FIG. 6, which is a schematicdiagram of a detecting device 60 according to an embodiment of thepresent invention. The detecting device 60 includes a low-pass filter602 and a logic circuit 604. Different with the detecting device 40 andthe detecting device 50, the logic circuit 604 includes a voltagefollower 606 and a processor 608. The voltage follower 606 has thecharacteristics that an input impedance is larger than an outputimpedance, and is utilized for avoiding impedance problems of a firstoutput voltage V1, which are caused by impedance mismatch between theresistor R1 and an input impedance effect of an ADC Input pin of theprocessor 608, and further affect the dc voltage level of the firstoutput voltage V1. Therefore, after the low-pass filter 602 generatesthe first output voltage V1 according to the PWM control signal, thevoltage follower 606 avoids the impedance problems, such that the dcvoltage level of the first output voltage V1 and an output voltage arecompletely identical. As a result, the dc voltage level of the firstoutput voltage V1 may be actually reflected on the ADC Input pin, i.e.the voltage level of the output voltage Vout is equal to that of thefirst output voltage V1. In this way, the processor 608 may directlydetermine the stack light state according to the digital signal of theADC Input pin corresponding to the dc voltage level of the first outputvoltage V1. In addition, the logic relations between the first outputvoltage V1, the output voltage Vout and the stack light state may beinducted and shown in Table 3.

TABLE 3 V1 = Vout The stack light state Vout ≥ V_(0.25 Hz) Persistent OnV_(0.25 Hz) > Vout ≥ V_(10 Hz) Twinkling V_(10 Hz) > Vout > VLPersistent Off

Based on different applications and design concepts, the detectingdevice of the present invention may be implemented in all kinds ofmethods. Furthermore, an operation method of the detecting device may beconcluded to a detecting method 70 as shown in FIG. 7, which includesthe following steps:

Step 702: Start.

Step 704: Perform the low-pass filtering on the PWM control signal, soas to generate the first output voltage V1.

Step 706: Determine the stack light state according to the first outputvoltage V1.

Step 708: End.

The operation of the detecting method 70 may be referred to the abovementioned embodiments of the detecting devices 10, 40, 50, 60, and isnot narrated herein for brevity.

Notably, those skilled in the art may properly design the detectingdevice according to different system requirements. For example, therange of the twinkling frequency of the stack light state, theimplementation method of the logic circuit, an amount of the voltagecomparator or the RC time constant of the low-pass filter may all beadjusted according to indications of a user or a manufacturer, orsettings of a computer system, and not limited thereto, which all belongto the scope of the present invention.

In summary, the present invention utilizes the PWM control signal of thestack light, the low-pass filter and the logic circuit for correctlydetermining the output signal of the twinkling stack light, so as toeffectively determine the stack light state and realize the detection ofthe stack light state in real-time.

Those skilled in the art will readily observe that numerousmodifications and alterations of the device and method may be made whileretaining the teachings of the invention. Accordingly, the abovedisclosure should be construed as limited only by the metes and boundsof the appended claims.

What is claimed is:
 1. A detecting device for detecting a stack lightstate, comprising: a low-pass filter configured to perform low-passfiltering on an input signal to generate a first output voltage; and alogic circuit coupled to the low-pass filter and configured to determinethe stack light state according to the first output voltage; wherein theinput signal is a pulse width modulation signal and a voltage level ofthe first output voltage is between a highest voltage level and a lowestvoltage level of the pulse width modulation signal.
 2. The detectingdevice of claim 1, wherein the low-pass filter generates the firstoutput voltage according to a variation frequency of the input signal.3. The detecting device of claim 2, wherein the logic circuit comprises:a voltage follower; and a processor coupled to the voltage follower andconfigured to determine the stack light state according to the firstoutput voltage.
 4. The detecting device of claim 3, wherein when thefirst output voltage is lower than or equal to a first voltage level,the processor determines that the stack light state is in a persistentoff state.
 5. The detecting device of claim 3, wherein when the firstoutput voltage is higher than a second voltage level, the processordetermines that the stack light state is in a persistent on state. 6.The detecting device of claim 3, wherein when the first output voltageis between the first voltage level and the second voltage level, theprocessor determines that the stack light state is in a twinkling state.7. The detecting device of claim 2, wherein the logic circuit comprises:a plurality of comparator circuits configured to generate a plurality oflogic results according to the first output voltage; and a processorcoupled to the plurality of comparator circuits and configured todetermine the stack light state according to the plurality of logicresults; wherein the plurality of logic results are related to arelationship between a first voltage level and a second voltage level.8. The detecting device of claim 7, wherein when the first outputvoltage is lower than or equal to the first voltage level, the processordetermines that the stack light state is in a persistent off state. 9.The detecting device of claim 7, wherein when the first output voltageis higher than the second voltage level, the processor determines thatthe stack light state is in a persistent on state.
 10. The detectingdevice of claim 7, wherein when the first output voltage is between thefirst voltage level and the second voltage level, the processordetermines that the stack light state is in a twinkling state.
 11. Adetecting method for detecting a stack light state, comprising:performing low-pass filtering on an input signal to generate a firstoutput voltage; and determining the stack light state according to thefirst output voltage; wherein the input signal is a pulse widthmodulation signal and a voltage level of the first output voltage isbetween a highest voltage level and a lowest voltage level of the pulsewidth modulation signal.
 12. The detecting method of claim 11, whereinperforming the low-pass filtering on the input signal is generating thefirst output voltage according to a variation frequency of the inputsignal.
 13. The detecting method of claim 11, wherein the step ofdetermining the stack light state according to the first output voltagecomprises: when the first output voltage is lower than or equal to afirst voltage level, determining that the stack light state is in apersistent off state.
 14. The detecting method of claim 11, wherein thestep of determining the stack light state according to the first outputvoltage comprises: when the first output voltage is higher than a secondvoltage level, determining that the stack light state is in a persistenton state.
 15. The detecting method of claim 11, wherein the step ofdetermining the stack light state according to the first output voltagecomprises: when the first output voltage is between the first voltagelevel and the second voltage level, determining that the stack lightstate is in a twinkling state.